Energy absorption of auxetic honeycomb with graded beam thickness based on Bezier curve

In order to improve the energy absorption and lightweight of the structure, a novel auxetic honeycomb with graded beam thickness based on Bezier curve (BZH) is proposed on the basis of the double arrow negative Poisson ratio honeycomb. The finite element model of BZH under axial compression is established, and its accuracy is verified by experiments. Compared with a honeycomb of uniform beam thickness (DUH) of the same mass, the thickness of the beam becomes thicker in the middle and thinner on both sides, which causes the BZH to produce more plastic hinges when compressed, and the energy absorption is increased by 12 %. By parameter analysis of beam thickness distribution trend, the mechanical properties of BZH can be effectively controlled. A theoretical model of BZH under quasi-static compression is also established and the BZH configuration is optimized by proxy modeling technique and NSGA-II algorithm. The results show that the SEA of the optimized structure is increased from 5.23 kJ·kg^-1 to 6.17 kJ·kg^-1, and the energy efficiency is reduced from 3.44 kN to 2.96 kN. Therefore, auxetic honeycomb with graded beam thickness based on Bezier curve has great potential in the field of energy absorption.